sweat

v.

Old English swætan "perspire, work hard," from the source of sweat (n.). Meaning "to be worried, vexed" is recorded from c.1400. Related: Sweated; sweating. Colloquial no sweat "no problem" attested from 1963.

The Dictionary of American Slang, Fourth Edition by Barbara Ann Kipfer, PhD. and Robert L. Chapman, Ph.D.Copyright (C) 2007 by HarperCollins Publishers.Cite This Source

Idioms and Phrases with sweat bullets

sweat bullets

Perspire profusely; also, suffer mental anguish. For example, We were sweating bullets, sitting in the sun through all those graduation speeches, or It was their first baby, and David was sweating bullets while Karen was in labor. The bullets in this expression allude to drops of perspiration the size of bullets.
[ ; mid-1900s
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